"Socio-ecological" factors are community-level social and other environmental characteristics that may influence an individual's utilization of cancer screening tests. This study will examine the effects of socio-ecological factors on population-based cancer screening behaviors, specifically for breast, cervix, colorectal and prostate cancers. Most importantly, this investigation focuses on identifying which socio-ecological conditions contribute to racial and ethnic differences in cancer screening. The specific aim of this study is to determine both individual and community-level effects that explain the sources of racial and ethnic differentials in access and utilization of cancer screening tests. I aim to accomplish this by (1) gathering and linking data at the individual-level, zip code-level and county-level that are relevant to cancer screening access and utilization; and, (2) with these data, constructing a multivariate multilevel model that predicts cancer screening utilization. The study will utilize individual-level data from the California Health Interview Survey 2001 (CHIS 2001 ) and socio-ecological variables drawn from a variety of sources. The CHIS 2001, conducted in English, Spanish, Cantonese, Mandarin, Korean, Vietnamese and Khmer, provides an excellent data source to measure the needs of minority populations and their immigrant subgroups. Reflecting California's "majority" minority population, the over 55,000 household survey collected information on unprecedented numbers of American Indians and Alaska Native, Asians, and Native Hawaiians and other Pacific Islanders. In addition, the survey collected information on over 10,000 Latinos and over 3,000 Blacks and African Americans. I will examine three domains of socio-ecological factors to assess their impact on individuals' utilization of cancer screening: (1) social resources, (2) health services, and (3) health insurance markets. In this multilevel framework, level 1 is measured at the individual level; it includes the dependent variable (i.e., utilization of a cancer screening test) and all associated individual-level characteristics such as socio-demographic information, health status and health insurance. Levels 2 and 3 reflect socio-ecological factors: level 2 consists of aggregate measures of social resources characteristics at the zip code-level, for example the proportion of households below poverty level, the percent of noncitizens, and the proportion of households with children; and level 3 includes county-level or county-group-level characteristics for health services and health insurance markets, for example percent of minority primary care physicians, the percent of oncologists and the per capita number of community health clinics. Combining health care market variables, with measures of social resources provides a comprehensive evaluation of the health system's mediating effect on promoting cancer screening behavior of minority communities. This work intends to contribute to the design of effective policy interventions targeted to both minority individuals and their communities.